Improvement in spark-arresters



A. MITCHELL,

SPARK-ARRESTER.

No.178,181. Patented May 30,1876.

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NAFTERS. PHOTDLITHOGRAFHEH, WSHINGTN. D C4 NITED 4vSTATES f.

PATENT rcE.

ALEXANDER MITCHELL," 0E wILKEsB'AEEE, PENNSYLVANIA.

IMPROVEMENT iN SPARK-ARRESTERS.'

.u Specification formingpart of Letters Patent No. 178,181, dated May 30, 1876 application tiled p April 26,1876.

To all whom. it may concern:

Beit known that I, ALEXANDER MITCHELL, of Wilkesbarre, Luzerne county, Pennsylvania, 'naveinvented an Improved Spark-Ar rester, of which the following is a specification:

The object vof my invention is toso construct a'spark-arrester for locomotives that the complete reduction and disposal of .the sparks is effected without obstructing the draft; and this object I attain in the manner which I will now proceed to describe, reference being had to the accompanying drawing, in which- Figurel is a transverse section of my improved spark-arrester, and Fig. 2 a view of a modification.

A is the` smokebox of a locomotive; B, the stack, and D the usual exhaust-pipe projecting up into the smoke-box from the bottom. Surrounding this pipe is a.'vertical tube, E, of somewhat greater diameter than the exhaustpipe, and this tube is preferably iared at its lower end, and projects down to within a short distance of the bottom of the smoke-box.

Surrounding the upper portion of the tube E is a screen, F, of wire-gauze or perforated plate, andmade in the shape of an inverted i'rustum of a cone, the lower end of this screen embracing the tube E near its lower end, and

the upper end ofthe screen being secured to a rib, a, formed on the upper portion of the smoke-box casing, and surrounding the mouth of the stack. Within the tubeE is arranged a perforated screen, G, also made in theshape `of an inverted f'rustum of a cone, the upper the screen F and out through thestack. Par-v ticles of' such ylarge size that they would be dangerous if thrown from the stack strike the screen, however, and, beiugtoo large t0 pass l through the openings ofthe saine, fall into the bottom of the smoke-box, and ,are drawn .up into the tube F and thrown forcibly against the screen G. The greater' portion of the sparks are so disintegrated by this treatment forded, while the escape of the exhaust-steam is entirely unobstructed. y

In Fig. 2a modilcation of my invention is shown, in which the tube E is increased in" diameter at E', and a horizontal screen, G', adapted to this enlarged portion, is used in place of the inclined screen shown in Fig. `1.

I.claim as my invention- The combination, in a spark-arrester, of the exhaust-pipe D, the tube E, the lower end of which extends nearly to the bottom ot' the smoke-box, with the screen F, arranged outside the tube E, and extending from the lower portion of the same to thetop of the smokebox, and the screen Gr, interposed between the pipe I) and the tube E, all substantially as set forth.

In testimony whereof Ihave signed my name to this specification in the presence of two subscribing witnesses.

ALEXANDER MITCHELL. 4Witnesses EDMUND G. BUTLER, GEO. A. WELLS. 

